South Korea's Joint Chiefs of Staff said it detected a new missile launch by North Korea, but did not provide details as it was awaiting analysis, according to Yonhap.

Japan's Defense Ministry also said the object launched by North Korea today could be a ballistic missile, according to Reuters.

North Korea has not yet announced the missile launch. The move comes after North Korea protested against a live-fire military exercise conducted by South Korea and the United States today, saying its forces would sternly respond to "any form of enemy protest or provocation," according to Reuters.

The drill was held at the Seungjin Firepower Training Area in Pocheon City, just 25 kilometers south of the inter-Korean border, to mark the 70th anniversary of the South Korea-US alliance and the 75th anniversary of the founding of the South Korean armed forces, according to Yonhap.

South Korean President Yoon Suk Yeol's office said the leader today oversaw the live-fire exercise, jointly organized by South Korean and US forces on the largest scale ever.

The exercise involved more than 610 military vehicles, including F-35A fighter jets and K9 self-propelled guns from the South Korean side, F-16 fighter jets and Grey Eagle drones from the US side, with the participation of more than 2,500 soldiers from 71 units from the South Korean and US sides.

The exercise, which began last month, consists of five phases. The first focuses on countering North Korea’s nuclear and missile threats and repelling a possible attack. The second part demonstrates the allies’ counterattack capabilities, according to Yonhap. The final phase will take place on June 15.